Draws by Insufficient Material There can never be a checkmate if the following material remains, even if the two players co-operate to attempt to mate one or other. (1) K v K (2) KN v K (3) KnB v KmB, where n & m are =< 9, and all bishops are operating on the same colour squares. Any other material in the open board permits a helpmate for at least one player. Historical note: These positions were (pre-1997) actually the "dead positions" under the FIDE Laws (except for the underpromotion cases). Then in 1997, the more generic dead position rule appeared, perhaps in the same spirit with which the 50 move rule was homogenized (to remove the exceptions) at that same time.